Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d59802f42c9f880…

MALICIOUS

PDF

80.8 KB Created: 2021-08-27 18:02:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a054c39e094abfb99ea9cf0a670ad3e3 SHA-1: 2ec2a67658b297e8e99010f930d7e414c58b75aa SHA-256: 4d59802f42c9f8806d8ba872de26b7086f0aaa63de9f1feb19662aa45b6538f2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to external sites, many of which are hosted on compromised CMS platforms or disposable domains. The presence of 'utm_term' parameters suggests a phishing or spam campaign aimed at driving traffic to these external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://queure.ru/uplcv?utm_term=6th+grade+cell+test+pdf PDF link annotation
    • https://nada70.org/userfiles/file/37098399984.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/motipogetitagipugop.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/li4t0oqpnr071gnfmum0d0vnk5/fizazeteritosoxetefer.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/c18ac2b4455826414ea4dc274507580a/futim.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d0bc960fdf---zewibevidu.pdfIn PDF document text
    • https://cedria.es/DOCUMENTS/FotosFCKEditor/file/tubexena.pdfIn PDF document text
    • http://aucoindeshalles.com/menu/file/54756929891.pdfIn PDF document text
    • http://tencanpowder.com/d/files/xemuvuzodege.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/64368004233.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/d5df878bc5b8b51bb60b13cc2ac6112e/92881146563.pdfIn PDF document text
    • http://akssert.com/userfiles/files/7306132794.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/42e9tt6shkmvhrmh9216j4sljh/lusaxitetegafazozigufil.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/im57kvir38gkcocad6n8bv92q2/zizogiguve.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b711e03e09b---23716346329.pdfIn PDF document text
    • http://boxerdapolenta.com/cmsimple/images/file/japotagugepapelabi.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/k6sl5fsk70mj2ni8au5v29361r/juzolozifike.pdfIn PDF document text
    • https://hotelgaric.com/upload/datoteke/95487373443.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611ad82f6ae81---46905017567.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160776b7584dc9---72316359233.pdfIn PDF document text
    • https://livres-d-art.com/ckfinder/userfiles/files/xepurepokopibozafupizinof.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/p2bj8k6dap17h7omjo8dff095e/14929040637.pdfIn PDF document text
    • http://utuin.net/files/fckeditor/file/soverojevaloxotiv.pdfIn PDF document text
    • http://hyderabadibiryanicorner.com/admin/images/file/mepegelavolilofekoj.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608515126da1a---21073544794.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/87744172544.pdfIn PDF document text
    • http://nirmalapublicschoolerumely.com/userfiles/file/31914752991.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d745.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD745 17156 bytes
SHA-256: f75dbd32bbb744384d4afeaf5a45ef14a6ff64d81b4e82e9887ee0a8896fe944
font_01_sfnt_off000103fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C11 10652 bytes
SHA-256: 9c1a1a3668e87c794ba9782020ee4ae20b24be15fd286d85c9327bf525724f1c